The present invention relates in general to an ergonomic support in the nature of chairs, sofas and the like, and more particularly, to such an ergonomic support having posterior and/or lumbar supporting portions which automatically conform to body movement without mechanical parts, as opposed to adjusting the body to comfortably conform to the posterior and lumbar supporting portions. Still more particularly, the posterior and/or lumbar supporting portions include non-planar contoured supporting surfaces shaped as compound curves, i.e., three-dimensional, thereby providing an effective ergonomic support for different body positions.
The art of designing body supports, in the nature of chairs and sofas having posterior and lumbar supporting portions, has thus far imperfectly take into consideration man's need to have a comfortable and flexible support which continuously conforms to different body positions. For example, chairs and sofas are known to be constructed from posterior and lumbar supporting assemblies consisting generally of a frame having a plurality of springs, a cushion or pad which rests on the springs, and an upholstery cover. These assemblies, although flexible due to their spring construction, assume a predetermined fixed shape which requires that man adjust his body position relative to these assemblies for maximum comfort. As chairs and sofas are a vital part of man's work and leisure environment, there is the need of providing a body support which is constructed to continuously conform to man's different body positions to provide maximum comfort.
Various structures have been proposed for posterior and lumbar supporting assemblies which are designed to possess increased flexiblity while providing body support. Such structures are known, for example, from U.S. Pat. Nos. 270,093, 2,804,129, 2,833,339, 3,399,883, 4,158,899 and 4,502,731. However, each of these structures merely provide an assembly having a plurality of openings to increase flexibility, rather than being designed in a manner which permits their continuous adjustment in conforming to different body positions to maximize comfort.
Other known structures have been designed as portable and collapsible chairs which include lumbar and posterior supporting portions constructed in the nature of serpentine-shaped members. Such structures are known, for example, from U.S. Pat. Nos. 4,533,174, 4,390,204 and 4,202,581. However, being portable and collapsible, these chairs are generally unsuitable both in construction and functionality in providing a comfortable support which can continuously conform to different body positions. In addition, these chairs are designed such that the serpentine-shaped members of the lumbar and posterior supporting portions are arranged to provide either a flat or non-contoured, planar supporting surface, i.e., simple curve. As a result, the serpentine-shaped members cannot sufficiently conform to the lumbar and posterior regions of a person when shifted to assume different body positions so as to provide an effective ergonomic support.
It can therefore be appreciated that there is an unsolved need for an ergonomic support in the nature of chairs, sofas and the like which, in addition to including flexible posterior and/or lumbar supporting portions having contoured supporting members, is constructed to continuously conform to different body positions to provide maximum comfort.